1 /* 2 * Hibernation support for x86-64 3 * 4 * Distribute under GPLv2 5 * 6 * Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl> 7 * Copyright (c) 2002 Pavel Machek <pavel@ucw.cz> 8 * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org> 9 */ 10 11 #include <linux/gfp.h> 12 #include <linux/smp.h> 13 #include <linux/suspend.h> 14 15 #include <asm/init.h> 16 #include <asm/proto.h> 17 #include <asm/page.h> 18 #include <asm/pgtable.h> 19 #include <asm/mtrr.h> 20 #include <asm/suspend.h> 21 22 /* References to section boundaries */ 23 extern __visible const void __nosave_begin, __nosave_end; 24 25 /* Defined in hibernate_asm_64.S */ 26 extern asmlinkage __visible int restore_image(void); 27 28 /* 29 * Address to jump to in the last phase of restore in order to get to the image 30 * kernel's text (this value is passed in the image header). 31 */ 32 unsigned long restore_jump_address __visible; 33 34 /* 35 * Value of the cr3 register from before the hibernation (this value is passed 36 * in the image header). 37 */ 38 unsigned long restore_cr3 __visible; 39 40 pgd_t *temp_level4_pgt __visible; 41 42 void *relocated_restore_code __visible; 43 44 static void *alloc_pgt_page(void *context) 45 { 46 return (void *)get_safe_page(GFP_ATOMIC); 47 } 48 49 static int set_up_temporary_mappings(void) 50 { 51 struct x86_mapping_info info = { 52 .alloc_pgt_page = alloc_pgt_page, 53 .pmd_flag = __PAGE_KERNEL_LARGE_EXEC, 54 .kernel_mapping = true, 55 }; 56 unsigned long mstart, mend; 57 int result; 58 int i; 59 60 temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC); 61 if (!temp_level4_pgt) 62 return -ENOMEM; 63 64 /* It is safe to reuse the original kernel mapping */ 65 set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map), 66 init_level4_pgt[pgd_index(__START_KERNEL_map)]); 67 68 /* Set up the direct mapping from scratch */ 69 for (i = 0; i < nr_pfn_mapped; i++) { 70 mstart = pfn_mapped[i].start << PAGE_SHIFT; 71 mend = pfn_mapped[i].end << PAGE_SHIFT; 72 73 result = kernel_ident_mapping_init(&info, temp_level4_pgt, 74 mstart, mend); 75 76 if (result) 77 return result; 78 } 79 80 return 0; 81 } 82 83 int swsusp_arch_resume(void) 84 { 85 int error; 86 87 /* We have got enough memory and from now on we cannot recover */ 88 if ((error = set_up_temporary_mappings())) 89 return error; 90 91 relocated_restore_code = (void *)get_safe_page(GFP_ATOMIC); 92 if (!relocated_restore_code) 93 return -ENOMEM; 94 memcpy(relocated_restore_code, &core_restore_code, 95 &restore_registers - &core_restore_code); 96 97 restore_image(); 98 return 0; 99 } 100 101 /* 102 * pfn_is_nosave - check if given pfn is in the 'nosave' section 103 */ 104 105 int pfn_is_nosave(unsigned long pfn) 106 { 107 unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT; 108 unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT; 109 return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); 110 } 111 112 struct restore_data_record { 113 unsigned long jump_address; 114 unsigned long cr3; 115 unsigned long magic; 116 }; 117 118 #define RESTORE_MAGIC 0x0123456789ABCDEFUL 119 120 /** 121 * arch_hibernation_header_save - populate the architecture specific part 122 * of a hibernation image header 123 * @addr: address to save the data at 124 */ 125 int arch_hibernation_header_save(void *addr, unsigned int max_size) 126 { 127 struct restore_data_record *rdr = addr; 128 129 if (max_size < sizeof(struct restore_data_record)) 130 return -EOVERFLOW; 131 rdr->jump_address = restore_jump_address; 132 rdr->cr3 = restore_cr3; 133 rdr->magic = RESTORE_MAGIC; 134 return 0; 135 } 136 137 /** 138 * arch_hibernation_header_restore - read the architecture specific data 139 * from the hibernation image header 140 * @addr: address to read the data from 141 */ 142 int arch_hibernation_header_restore(void *addr) 143 { 144 struct restore_data_record *rdr = addr; 145 146 restore_jump_address = rdr->jump_address; 147 restore_cr3 = rdr->cr3; 148 return (rdr->magic == RESTORE_MAGIC) ? 0 : -EINVAL; 149 } 150